[BerntR]

The GW and SW are Titleist Vokeys. The PW and on are Mizuno MP 32. The Mizunos hare progressively flattened towards the long irons. The PW has stock lie angle. The PW is 1/2 inch longer than the GW and sits more upright at address. That seems to make a big difference.

I am sure the lie angle has a lot to do with what I am experiencing. Gripping down has very similar implications as playing with flatter lies. If you grip down an inch with a 5 iron you're playing a club with 5 iron lie angle and 7 iron shaft length. This is a very real difference. Right now I'm also thinking that it is easier to fade the ball if you grip down on the club. I'm certainly going to experiment further with this. And I will probably get flatter lies the next time around.

But I am also starting to wonder whether the redistribution of weight that occurs when you grip down has a significant impact. It will put more mass in the hands and less "dynamic" mass in the clubhead.